Third-trimester ultrasound for antenatal diagnosis of placenta accreta spectrum in women with placenta previa: results from the ADoPAD study.

OBJECTIVE: To evaluate the performance of third-trimester ultrasound for the diagnosis of clinically significant placenta accreta spectrum disorder (PAS) in women with low-lying placenta or placenta previa. METHODS: This was a prospective multicenter study of pregnant women aged ≥ 18 years who were diagnosed with low-lying placenta (< 20 mm from the internal cervical os) or placenta previa (covering the internal cervical os) on ultrasound at ≥ 26 + 0 weeks' gestation, between October 2014 and January 2019. Ultrasound suspicion of PAS was raised in the presence of at least one of these signs on grayscale ultrasound: (1) obliteration of the hypoechogenic space between the uterus and the placenta; (2) interruption of the hyperechogenic interface between the uterine serosa and the bladder wall; (3) abnormal placental lacunae. Histopathological examinations were performed according to a predefined protocol, with pathologists blinded to the ultrasound findings. To assess the ability of ultrasound to detect clinically significant PAS, a composite outcome comprising the need for active management at delivery and histopathological confirmation of PAS was considered the reference standard. PAS was considered to be clinically significant if, in addition to histological confirmation, at least one of these procedures was carried out after delivery: use of hemostatic intrauterine balloon, compressive uterine suture, peripartum hysterectomy, uterine/hypogastric artery ligation or uterine artery embolization. The diagnostic performance of each ultrasound sign for clinically significant PAS was evaluated in all women and in the subgroup who had at least one previous Cesarean section and anterior placenta. Post-test probability was assessed using Fagan nomograms. RESULTS: A total of 568 women underwent transabdominal and transvaginal ultrasound examinations during the study period. Of these, 95 delivered in local hospitals, and placental pathology according to the study protocol was therefore not available. Among the 473 women for whom placental pathology was available, clinically significant PAS was diagnosed in 99 (21%), comprising 36 cases of placenta accreta, 19 of placenta increta and 44 of placenta percreta. The median gestational age at the time of ultrasound assessment was 31.4 (interquartile range, 28.6-34.4) weeks. A normal hypoechogenic space between the uterus and the placenta reduced the post-test probability of clinically significant PAS from 21% to 5% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 9% in the subgroup with previous Cesarean section and anterior placenta. The absence of placental lacunae reduced the post-test probability of clinically significant PAS from 21% to 9% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 36% in the subgroup with previous Cesarean section and anterior placenta. When abnormal placental lacunae were seen on ultrasound, the post-test probability of clinically significant PAS increased from 21% to 59% in the whole cohort and from 62% to 78% in the subgroup with previous Cesarean section and anterior placenta. An interrupted hyperechogenic interface between the uterine serosa and bladder wall increased the post-test probability for clinically significant PAS from 21% to 85% in women with low-lying placenta or placenta previa and from 62% to 88% in the subgroup with previous Cesarean section and anterior placenta. When all three sonographic markers were present, the post-test probability for clinically significant PAS increased from 21% to 89% in the whole cohort and from 62% to 92% in the subgroup with previous Cesarean section and anterior placenta. CONCLUSIONS: Grayscale ultrasound has good diagnostic performance to identify pregnancies at low risk of PAS in a high-risk population of women with low-lying placenta or placenta previa. Ultrasound may be safely used to guide management decisions and concentrate resources on patients with higher risk of clinically significant PAS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Treatment of Graves' hyperthyroidism with thionamides: a position paper on indications and safety in pregnancy.

CONTEXT: Graves' disease affects 3% of women and 0.5% of men in the general population. The first line treatment of Graves' hyperthyroidism is based on the administration of antithyroid drugs (ATD), propylthiouracil (PTU), methimazole (MMI) and carbimazole. A recent warning from the Italian Drug Agency (Agenzia Italiana del Farmaco AIFA) reported the risk of MMI-induced acute pancreatitis. In addition, AIFA highlighted the possible association of MMI treatment during the first trimester of pregnancy with congenital malformations, thus recommending the use of effective contraceptive methods in women of childbearing age treated with MMI. METHODS AND RESULTS: Revision of literature reported less than ten cases of the alleged MMI pancreatitis, allowing the inclusion of MMI in class III drug regarding the relative risk for drug-induced pancreatitis. Data available on the effect of hyperthyroidism per se on the risk of fetal malformations, although scanty, are sufficient to recommend treatment with ATD of the hyperthyroid pregnant woman. Case reports and population studies either suggesting or not suggesting MMI-induced fetal malformations do not allow unquestionable conclusions on this matter. CONCLUSIONS: This consensus by experts from Italian Endocrine and Gynecologic Scientific Societies has edited recommendations derived form the available data and published guidelines of International Scientific Societies.

Locally advanced cervical cancer complicating pregnancy: A case of competing risks from the Catholic University of the Sacred Heart in Rome.

A case of stage IB2 cervical cancer at 27 weeks of pregnancy, treated with neoadjuvant chemotherapy followed by radical Cesarean hysterectomy with full pelvic and infra-mesenteric lymphadenectomy, and adjuvant chemo-radiation is described. While she remains without disease, her baby was diagnosed with acute myelogenous leukemia. We highlight the pre-operative work-up, treatment options, safety, feasibility, and outcomes for the mother and her fetus.

Amniocentesis and chorionic villus sampling in HIV-infected pregnant women: a multicentre case series.

OBJECTIVES: To assess in pregnant women with HIV the rates of amniocentesis and chorionic villus sampling (CVS), and the outcomes associated with such procedures. DESIGN: Observational study. Data from the Italian National Program on Surveillance on Antiretroviral Treatment in Pregnancy were used. SETTING: University and hospital clinics. POPULATION: Pregnant women with HIV. METHODS: Temporal trends were analysed by analysis of variance and by the Chi-square test for trend. Quantitative variables were compared by Student's t-test and categorical data by the Chi-square test, with odds ratios and 95% confidence intervals calculated. MAIN OUTCOME MEASURES: Rate of invasive testing, intrauterine death, HIV transmission. RESULTS: Between 2001 and 2015, among 2065 pregnancies in women with HIV, 113 (5.5%) had invasive tests performed. The procedures were conducted under antiretroviral treatment in 99 cases (87.6%), with a significant increase over time in the proportion of tests performed under highly active antiretroviral therapy (HAART) (100% in 2011-2015). Three intrauterine deaths were observed (2.6%), and 14 pregnancies were terminated because of fetal anomalies. Among 96 live newborns, eight had no information available on HIV status. Among the remaining 88 cases with either amniocentesis (n = 75), CVS (n = 12), or both (n = 1), two HIV transmissions occurred (2.3%). No HIV transmission occurred among the women who were on HAART at the time of invasive testing, and none after 2005. CONCLUSIONS: The findings reinforce the assumption that invasive prenatal testing does not increase the risk of HIV vertical transmission among pregnant women under suppressive antiretroviral treatment. TWEETABLE ABSTRACT: No HIV transmission occurred among women who underwent amniocentesis or CVS under effective anti-HIV regimens.

Investigation on the role of consumer health orientation in the use of food labels.

OBJECTIVE: This study explored the relationship between health orientation (i.e. individual motivation to engage in healthy attitudes, beliefs and behaviours) and consumers' use of nutritional information on food labels. Specifically, this study analysed the relationship between a number of direct investments in health (namely those behaviours that can contribute directly to maintain a good health status) and use of nutritional information on food labels. STUDY DESIGN: Data for the analysis were collected through face-to-face interviews with a sample of 540 Italian consumers in charge of their grocery shopping. Forty grocery stores, including supermarkets and hypermarkets, were selected using a systematic sampling technique. METHODS: Data were analysed using three equations and accounting for endogeneity issues. RESULTS: This study found that those consumer groups with low health orientation (specifically smokers, those who do not exercise regularly, and those with an unhealthy body weight) show little interest in nutritional labels. CONCLUSION: Nutritional labels as a tool to promote healthier food choices have a limited effect on those consumers in greatest need of pursuing healthier lifestyle habits. Alternative policy intervention should be undertaken to reach these consumer groups.

Snip conjunctivoplasty associated with methylene blue staining for treatment of postoperative conjunctival chemosis.

Conjunctival chemosis usually undergoes spontaneous resolution; sometimes, it requires treatment. We present the case of a 43 years-old female patient who developed bilateral conjunctival chemosis following upper and lower blepharoplasty. Two months after the operation, patient underwent bilateral snip conjunctivoplasty with methylene blue demarcation of the chemotic conjunctiva.

Evolution of echocardiographic and cardiac magnetic resonance imaging abnormalities during follow-up in patients with multisystem inflammatory syndrome in children.

AIMS: Multisystem inflammatory syndrome in children (MIS-C) with cardiovascular manifestations are frequent. However, there is lacking evidence regarding cardiological follow-up of this cohort of patients. The aim of our study was to describe the early and mid-term cardiac abnormalities assessed by standard and speckle-tracking echocardiography (STE), and cardiac MRI (CMR). METHODS AND RESULTS: We enrolled 32 patients (21 male, 11 female), mean age 8.25 ± 4years, with diagnosis of MIS-C. During admission, all children underwent TTE, STE with analysis of left ventricle global longitudinal strain (GLS) and CMR. Patients underwent cardiological evaluation at 2 (T1) and 6 months (T2) after discharge. Cardiac MRI was repeated at 6 months after discharge. Mean left ventricular ejection fraction (LVEF) at baseline was 58.8 ± 10% with 10 patients (31%) below 55%. Speckle-tracking echocardiography showed reduced mean LV GLS (-17.4 ± 4%). On CMR, late gadolinium enhancement (LGE) with non-ischaemic pattern was evident in 8 of 23 patients (35%). Follow-up data showed rapid improvement of LVEF at T1 (62.5 ± 7.5 vs. 58.8 ± 10.6%, P-value 0.044) with only three patients (10%) below ≤ 55% at T1. Left ventricular (LV) GLS remained impaired at T1 (-17.2 ± 2.7 vs.-17.4 ± 4, P-value 0.71) and significantly improved at T2 (-19 ± 2.6% vs. -17.4 ± 4%, P-value 0.009). LV GLS was impaired (>-18%) in 53% of patients at baseline and T1, whereas only 13% showed persistent LV GLS reduction at T2. Follow-up CMR showed LGE persistence in 33.4% of cases. CONCLUSION: Early cardiac involvement significantly improves during follow-up of MIS-C patients. However, subclinical myocardial dysfunction seems to be still detectable after 6 months of follow-up in a not negligible proportion of them.

Risk factors for relapse after conservative treatment in T1-T2 breast cancer with one to three positive axillary nodes: results of an observational study.

BACKGROUND: As few data are available on irradiation of the draining nodes after conservative surgery (CS), this study was designed to identify patients with T1-T2 breast cancer and one to three positive axillary nodes who needed regional radiotherapy (RT). PATIENTS AND METHODS: Five hundred seventy-five patients were treated between 1988 and 2001 with CS and RT to the breast. All but three received adjuvant chemotherapy and/or hormone therapy. Risk factors for and the relationships between local, nodal and distant relapses were analyzed. RESULTS: At a median follow-up of 7.3 years, the 10-year probability of survival free of local relapse, nodal relapse and distant metastases were 92.8%, 94.0% and 84.9%, respectively. Independent predictors of local relapse were the positive/excised node ratio, margin status and age. Predictors of nodal relapse were tumor grade, hormone receptor and margin status. Significant risk factors for distant metastases were tumor stage, grade, hormone receptor and margin status. Local and nodal relapses were related significantly with distant metastases. Only local and distant relapses were linked by temporal sequence (P=0.03). CONCLUSIONS: Overall relapse rates were low in these patients and different mechanisms appeared to underlie local, nodal or distant relapse.

Chemotherapy toxicity and activity in patients with pancreatic ductal adenocarcinoma and germline BRCA1-2 pathogenic variants (gBRCA1-2pv): a multicenter survey.

BACKGROUND: Germline BRCA1-2 pathogenic variants (gBRCA1-2pv)-related pancreatic ductal adenocarcinoma (PDAC) showed increased sensitivity to DNA cross-linking agents. This study aimed at exploring safety profile, dose intensity, and activity of different chemotherapy regimens in this setting. PATIENTS AND METHODS: gBRCA1-2pv PDAC patients of any age and clinical tumor stage who completed a first course of chemotherapy were eligible. A descriptive analysis of chemotherapy toxicity, dose intensity, response, and survival outcomes was performed. RESULTS: A total of 85 gBRCA1-2pv PDAC patients treated in 21 Italian centers between December 2008 and March 2021were enrolled. Seventy-four patients were assessable for toxicity and dose intensity, 83 for outcome. Dose intensity was as follows: nab-paclitaxel 72%, gemcitabine 76% (AG); cisplatin 75%, nab-paclitaxel 73%, capecitabine 73%, and gemcitabine 65% (PAXG); fluorouracil 35%, irinotecan 58%, and oxaliplatin 64% (FOLFIRINOX). When compared with the literature, grade 3-4 neutropenia, thrombocytopenia, and diarrhea were increased with PAXG, and unmodified with AG and FOLFIRINOX. RECIST responses were numerically higher with the three- (81%) or four-drug (73%) platinum-containing regimens that outperformed AG (41%) and oxaliplatin-based doublets (56%). Carbohydrate antigen 19.9 (CA19.9) reduction >89% at nadir was reported in two-third of metastatic patients treated with triplets and quadruplets, as opposed to 33% and 45% of patients receiving oxaliplatin-based doublets or AG, respectively. All patients receiving AG experienced disease progression, with a median progression-free survival (mPFS) of 6.4 months, while patients treated with platinum-containing triplets or quadruplets had an mPFS >10.8 months. Albeit still immature, data on overall survival seemed to parallel those on PFS. CONCLUSIONS: Our data, as opposed to figures expected from the literature, highlighted that platinum-based regimens provoked an increased toxicity on proliferating cells, when dose intensity was maintained, or an as-expected toxicity, when dose intensity was reduced, while no change in toxicity and dose intensity was evident with AG. Furthermore, an apparently improved outcome of platinum-based triplets or quadruplets over other regimens was observed.

Germinal BRCA1-2 pathogenic variants (gBRCA1-2pv) and pancreatic cancer: epidemiology of an Italian patient cohort.

OBJECTIVE: Germline BRCA1-2 pathogenic variants (gBRCApv) increase the risk of pancreatic cancer and predict for response to platinating agents and poly(ADP-ribose) polymerase inhibitors. Data on worldwide gBRCApv incidence among pancreatic ductal adenocarcinoma (PDAC) patients are sparse and describe a remarkable geographic heterogeneity. The aim of this study is to analyze the epidemiology of gBRCApv in Italian patients. MATERIALS AND METHODS: Patients of any age with pancreatic adenocarcinoma, screened within 3 months from diagnosis for gBRCApv in Italian oncologic centers systematically performing tests without any selection. For the purposes of our analysis, breast, ovarian, pancreas, and prostate cancer in a patient's family history was considered as potentially BRCA-associated. Patients or disease characteristics were examined using the χ2 test or Fisher's exact test for qualitative variables and the Student's t-test or Mann-Whitney test for continuous variables, as appropriate. RESULTS: Between June 2015 and May 2020, 939 patients were tested by 14 Italian centers; 492 (52%) males, median age 62 years (range 28-87), 569 (61%) metastatic, 273 (29%) with a family history of potentially BRCA-associated cancers. gBRCA1-2pv were found in 76 patients (8.1%; 9.1% in metastatic; 6.4% in non-metastatic). The gBRCA2/gBRCA1 ratio was 5.4 : 1. Patients with gBRCApv were younger compared with wild-type (59 versus 62 years, P = 0.01). The gBRCApv rate was 17.1% among patients <40 years old, 10.4% among patients 41-50 years old, 9.2% among patients 51-60 years old, 6.7% among patients aged 61-70 years, and 6.2% among patients >70 years old (none out of 94 patients >73 years old). gBRCApv frequency in 845 patients <74 years old was 9%. Patients with/without a family history of potentially BRCA-associated tumors had 14%/6% mutations. CONCLUSION: Based on our findings of a gBRCApv incidence higher than expected in a real-life series of Italian patients with incident PDAC, we recommend screening all PDAC patients <74 years old, regardless of family history and stage, due to the therapeutic implications and cancer risk prevention in patients' relatives.

High coexpression of both insulin-like growth factor receptor-1 (IGFR-1) and epidermal growth factor receptor (EGFR) is associated with shorter disease-free survival in resected non-small-cell lung cancer patients.

BACKGROUND: Insulin-like growth factor receptor-1 (IGFR-1) represents a novel molecular target in non-small-cell lung cancer (NSCLC). IGFR-1 and epidermal growth factor receptor (EGFR) activation is essential to mediate tumor cell survival, proliferation and invasion. We explored the correlation between IGFR-1 and EGFR, their relationship with clinicopathological parameters and their impact on outcome in resected stage I-III NSCLC patients. PATIENTS AND METHODS: Tumors from 125 surgical NSCLC patients were evaluated for IGFR-1 and EGFR expression by immunohistochemistry. Kaplan-Meier estimates of survival and time to recurrence were calculated for clinical variables and biologic markers using the Cox model for multivariate analysis. RESULTS: IGFR-1 protein overexpression was detected in 36.0% of NSCLC patients and was associated with larger tumor size (P = 0.04) but not with other clinical or biological characteristics. EGFR protein overexpression was observed in 55.2% of NSCLC, more frequently in squamous cell carcinoma (SCC) than non-SCC (63.7% versus 36.3%, chi(2) = 9.8, P = 0.001). IGFR-1 protein expression was associated with EGFR protein expression (P = 0.03). At the multivariate analysis, high coexpression of both IGFR-1 and EGFR was a significant prognostic factor of worse disease-free survival (DFS) (hazard ratio 2.51, P = 0.01). CONCLUSION: A statistically significant association was observed between high coexpression of both IGFR-1 and EGFR and worse DFS in early NSCLC patients.

Rapidly changing radio images.

Differences in total transit time can give rise to images that expand at arbitrarily high speed. Two versions of a model based on this idea can account for the varying microwave structure reported for the quasar 3C 279. Other possible examples are suggested.

A useful ultrasound score to select thyroid nodules requiring fine needle aspiration in an iodine-deficient area.

BACKGROUND: The high prevalence of thyroid nodules in iodine-deficient areas is a practical problem because of the large number of patients requiring fine needle aspiration (FNA) to detect malignant nodules. AIM: To obtain an ultrasound (US) score for predicting malignant nodules and reduce the number of unnecessary and expensive FNA. SUBJECT AND METHOD: All nodules observed from September 2001 to March 2006 were evaluated by US: echostructure, echogenicity, halo, microcalcifications and ratio between antero-posterior and transversal diameters (AP/TR). Two thousand six hundred and forty-two consecutive patients underwent US-guided FNA for a total of 3645 nodules. RESULTS: Logistic regression analysis showed a potent predictive role for solitary nodules and absence/ incomplete halo (p=0.000). A significant predictive role for microcalcifications and AP/TR ratio was also observed. A 10-point score was constructed using the standardized regression coefficient. Nodules with US score or=5.5 had a frequency of malignancy of 0.4, 1.1 and 5.6% (p<0.001), respectively. Nodules with >or=5.5 US score were characterized by a 66% sensitivity and a 76% specificity compared to the diagnostic values of single parameters which were either sensitive or specific. CONCLUSIONS: According to our data, we suggest FNA for nodules reaching a >5.4 US score, whereas a clinical judgement should be used for the intermediate category nodules. When the score is lower than 2.5 we do not recommend FNA. The practical use of this US score can help reduce unnecessary and expensive FNA in iodine-deficient areas.

Lack of inflammatory cells in the oral mucosa of subjects undergoing sublingual immunotherapy.

The cells involved in allergic inflammation, such as mast cells, basophils, and eosinophils, have been thoroughly studied in the nose, the lungs and the skin, demonstrating an evident increase in response to the introduction of the specific allergen, while little is known in the mucosal system and particularly in the oral mucosa. We investigated such tissue by using the model of sublingual immunotherapy (SLIT), by which high doses of the specific allergen enter the mouth. Oral biopsies were carried out on seven subjects allergic to grass pollen and treated with SLIT by a grass extract. In biopsies carried out before SLIT there was a very low number of mast cells and eosinophils both in the epithelium and subepithelium layers, and insignificant changes were detected after SLIT. These findings show the lack of allergic inflammation in the oral mucosa upon contact with the specific allergen and confirm the role of the mouth as a tolerogenic site, which is conceivable considering the different attitude of the mouth, where the antigens transit to undergo digestion, in respect to the airways or the skin, where the antigen absorption is potentially dangerous.

Fine needle aspiration cytology of thyroid nodules: conventional vs thin layer technique.

OBJECTIVE: Liquid-based cytology using the thin layer technique has recently been introduced in thyroid fine needle aspiration cytology together with or in substitution of direct smears, but its usefulness is still controversial and relatively few studies have been published in this field. The aim of the present study was to compare the results obtained from conventional smears with those from thin layer smears. DESIGN: In 3875 thyroid nodules, a double cytologic sampling was taken in randomized order, to prepare conventional or thin layer smears. MAIN OUTCOME: The diagnoses agreed in 2934 (75.7%) cases and disagreed in 941 (24.3%). The analysis of discordant data showed there were fewer non-diagnostic cases in the thin layer smears (377 vs 541, p<0.001) whereas in conventional smears there were more cases positive for carcinoma (27 vs 4, p<0.001). The cytohistologic correlation was available for 194 cases and showed that conventional smears had a greater capacity for revealing carcinomas (44 vs 31). Finally, diagnoses based on conventional smears were more sensitive than thin layer smears (93.6% vs 65.9%) whereas specificity was constant. CONCLUSIONS: From our experience, the conventional smear offers a greater possibility of diagnosis when suspecting malignancy or diagnosing malignancy cases, whereas thin layer smears significantly reduce the number of non-diagnostic cases. For this reason, we suggest combining the two techniques in routine cytologic diagnosis.

Recurrences of thyroid well differentiated cancer: ultrasonography-guided surgical treatment.

AIM: Differentiated thyroid carcinomas (DTC) have a favourable outlook overall. Cornerstone of treatment is total thyroidectomy (TT), followed, if needed, by radiometabolic therapy. Such lesions however show a definite tendency to recur (about 35% of cases), generally in the first decade of follow-up: in 70% of patients such recurrence is local. Surgical resection is the only curative treatment option for local recurrence of well-differentiated thyroid cancer. Intraoperative ultrasonography (US) can be of significant help in facilitating localization and complete resection of lesions. The aim of the study was to review the authors' own experience with the use of such diagnostic method in the clinical setting of thyroid neoplasm recurrence. METHODS: Between January 2005 and March 2008 31 patients with DTC recurrences underwent intraoperative US exploration. Recurrences were easily identified and resected in all patients. Postoperative tireoglobuline (TG) was undetectable. RESULTS: In all 31 patients preoperative US confirmed the presence of the lesion. In 26 patients digital exploration of the surgical field did not yield a definitively positive finding, whereas in 5 the lesion was easily palpable. Intraoperative US revealed the presence of pathologic tissue in all cases, with examination time ranging from 4 to 14 minutes (median 8 minutes). In all cases surgical resection was complete, with pathologic confirmation of the sample, and no necessity to extend ablation. CONCLUSION: Intraoperative US can be of significant help in the identification of DTC recurrences, in particular when lesion dimensions are smaller than 10 mm in diameter and can facilitate a more radical excision of the tumor in a surgical field were anatomical landmarks can be altered by previous surgery and/or radiometabolic therapy.

Retroperitoneal abscess: an uncommon localization of tubercular infection.

We describe a rare case of a 29-year-old immunocompetent Nigerian male affected by an abdominal abscess due to Mycobacterium tuberculosis infection. Diagnosis was achieved with cultures from surgical drainage. No pulmonary, renal, or gastrointestinal involvement was identified. The patient was successfully treated with standard four-drug antitubercular therapy.

Biochemical and molecular characterization of the novel BRAF(V599Ins) mutation detected in a classic papillary thyroid carcinoma.

Activating mutations of the BRAF gene are the most common genetic alterations in papillary thyroid carcinomas (PTCs) and the T1799A transversion, resulting in BRAFV600E, appeared virtually unique in this cancer type. Here, we report on the identification in a classic PTC of a novel BRAF mutation, namely a 1795GTT insertion, resulting in BRAFV599Ins, and describe its biochemical and molecular characterization. Kinase assays carried out on BRAFV599Ins and BRAFV600E revealed a three- to five-fold increase in the enzymatic activity of both mutants with respect to BRAFWT. Similarly, evaluation of BRAF-induced phosphorylation of MEK, MAPK and RSK revealed a significant MAPK cascade activation in cells expressing BRAFV599Ins or BRAFV600E, but not in cells expressing BRAFWT. Molecular dynamic simulations showed a destabilization of the inactive conformation of the enzyme in both BRAFV599Ins and BRAFV600E mutants, but not in BRAFWT. The analysis of the interaction energies inside the catalytic site allowed to demonstrate the presence of repulsive electrostatic forces acting on the activation loop and moving from inward to outward of the mutant enzymes. Finally, focus assays in NIH-3T3 cells confirmed a high transformation rate in the cells transfected either with BRAFV599Ins or BRAFV600E. In conclusion, this study demonstrated that BRAFV599Ins, as BRAFV600E, is a 'gain of function' mutation, characterized by a constitutive catalytic activation, which accounts for its causative role in the studied PTC.